I wish to buy a second battery for my Canon EOS 1D MKII. I was wondering if anyone in the forum could share any experiences they might have had with the Energizer ER-D140. Here is a link to it on the Energizer site:

The page says "coming soon" but the pack is already available by mail order at a price that's about a third or so of the NP-E3. I've heard that many of the "compatible" packs didn't fare so well quality-wise but my good experiences with Energizer in the past has prompted me to investigate further.